Performing a Network
Assessment of the Infrastructure
Having read the previous sections, it should be crystal clear that performing an
assessment of the network infrastructure is not only vital to the success of the
VoIP installation, but also to the continued success of the installation. Using the
word “assessment” often conjures up impressions of tens of thousands of dollars in
consultant expenses, but it doesn’t have to be.The tasks carried out most often in
an assessment of this degree are as follows:
1. Test and validate the network wiring to assure it’s at least category-5-
compliant, without faults or errors.
2. Review and document the existing network electronics to determine
what make, model, and part number of the device is installed.This will
be used to determine the lateral Cisco replacement part, as a minimum,
although a somewhat higher level of functionality is usually required.
3. Review and document the current telephony solution to determine
exactly which portions of PBX is to be replaced, augmented, or supplemented
with VoIP services.The current user’s dial plan should be clearly
documented and understood so that the correct VoIP dialing architecture
can be designed.
4. Lastly, determine exactly which telephony services are required, such as
voice and fax.You’ll specifically need this since, from a technical standpoint,
a fax call is merely another form of using one 64 Kbps channel of
communications. If you have to dedicate a channel for a fax, you’re
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354 Chapter 10 • Designing and Implementing Single Site Solutions
better off using a dedicated fax line instead of one of the channels previously
mentioned.
From this simple list, you should now understand why an assessment is
needed at one site and not needed at other locations, while still yet other sites
may need only a partial site review. A customer’s needs will vary between desires
of using VoIP and/or AVVID solutions, but the review will just make sure that no
one is caught unaware of special circumstances that may cloud the overall design.